Morton's Neuroma What Is It?
A Morton's neuroma is a benign (noncancerous) swelling along a nerve in the foot that carries sensations from the toes. The reason the nerve starts to swell is unknown. But once swelling begins, the nearby bones and ligaments put pressure on the nerve, causing more irritation and inflammation. This produces burning pain, numbness, tingling and other abnormal sensations in the toes. A Morton's neuroma also is called an interdigital neuroma, intermetatarsal neuroma or a forefoot neuroma.
A Morton's neuroma usually develops between the third and fourth toes. Less commonly, it develops between the second and third toes. Other locations are rare. It also is rare for a Morton's neuroma to develop in both feet at the same time. The condition is much more common in women than men, probably as a result of wearing high-heeled, narrow-toed shoes. This style of shoe tends to shift the bones of the feet into an abnormal position, which increases the risk that a neuroma will form. Being overweight also increases the risk of a Morton's neuroma.Symptoms
A Morton's neuroma usually causes burning pain, numbness or tingling at the base of the third, fourth or second toes. Pain also can spread from the ball of the foot out to the tips of the toes. In some cases, there also is the sensation of a lump, a fold of sock or a "hot pebble" between the toes.
Typically, the pain of a Morton's neuroma is relieved temporarily by taking off your shoes, flexing your toes and rubbing your feet. Symptoms may be aggravated by standing for prolonged periods or by wearing high heels or shoes with a narrow toe box.Diagnosis
Your doctor will suspect that you have a Morton's neuroma based on the nature and location of your foot pain. He or she may ask questions about your shoes — what type of shoes you usually wear and whether these shoes have narrow toes or high heels. To rule out other causes of foot pain, your doctor may ask questions about your medical history, especially any history of arthritis, nerve and muscle problems or previous injury to your foot or leg.
To confirm the diagnosis, your doctor will examine your feet. He or she will look for areas of tenderness, swelling, calluses, numbness, muscle weakness and limited motion. To check for a Morton's neuroma, your doctor will squeeze the sides of your foot. Squeezing should compress the neuroma and trigger your typical pain. In some cases, your doctor will find numbness in the webbed area between the affected toes. Pain in two or more locations on one foot, such as between both the second and third toes and the third and fourth toes, more likely indicates that the toe joints are inflamed rather than a Morton' neuroma.
Based on the physical examination, your doctor usually can diagnose a Morton's neuroma without additional testing. A foot X-ray may be ordered to make sure that there isn't a stress fracture, but it will not show the actual neuroma. If the diagnosis is in doubt, your doctor may request magnetic resonance imaging (MRI) of the foot.Expected Duration
A Morton's neuroma will not disappear on its own. Usually, the symptoms will come and go, depending on the type of shoes you wear and how much time you spend on your feet. Sometimes, the symptoms will go away completely.Prevention
It is not always possible to prevent a Morton's neuroma. However, you probably can reduce your risk by wearing comfortable shoes
that have low heels, plenty of toe space and good arch support.Treatment
If your Morton's neuroma is painful, your doctor usually will begin treatment with conservative therapies, including: A switch to shoes with low heels, wide toes and good arch support
Padding techniques, including metatarsal pads or toe crest pads
Shoe inserts (orthotics) to help correct any mechanical imbalance in the foot
Anti-inflammatory medication, such as ibuprofen (Advil, Motrin and other brand names) or naproxen (Aleve, Naprosyn and other brand names)
A local injection of anesthetic and corticosteroid medication into the affected area
Inflamed or injured nerves can take months to improve, even after the underlying problem has been corrected. If your pain continues despite several months of conservative treatment, your doctor may recommend surgery to remove the neuroma or to widen the space through which the affected nerve travels. These types of surgery often are done under local anesthesia. If your doctor removes a portion of the affected nerve along with the neuroma, you may develop permanent numbness between the toes.
When To Call A Professional
Make an appointment to see a podiatrist if you have symptoms of a Morton's neuroma that do not improve when you wear comfortable, wide shoes.
More than 80% of people with a Morton's neuroma will respond to conservative treatment. For the minority of people who have persistent, disabling symptoms, surgery may be an option.
Printed with permission from Harvard Medical School. (September 22, 2005)